LESSON OBJECTIVES: Distinguish between speed and velocity using the concept of vectors ; Differentiate speed from velocity and solve problems involving speed and velocity
SPEED Speed is a measure of how fast something is moving. It is the rate at which distance is covered. The word rate is a clue that something is being divided by time . Speed is defined as the distance covered per unit time. Speed is also a scalar quantity .
SPEED
VELOCITY Velocity is a vector quantity. It describes how fast and in which way (speed + direction) an object is moving. It can be negative or positive depending on the direction of motion.
VELOCITY
Differentiate Speed from Velocity Speed (v) v = d/t = 150 m /15 s = 10 m/s velocity ( v ) v = d / t = 50 m, E/15 s = 3.33 m/s, E
Sample Problem: 1. A car moves at a velocity of 60 km/ hr , West for 5 hours, how far will it go? Given: velocity = 60 km/ hr , W Required: displacement time = 5 hrs Formula: displacement= velocity x time Solution: displacement=60 km/ hr,West x 5 hrs displacement = 300 km/ West The car will reach 300 km, West at a velocity of 60 km/hr.
2. A train needs to travel a distance of 30 miles at a speed of 10 mi/hr. How long will it take the train to reach its destination? Given: distance =30 mi speed = 10 mi/ hr Required: time Formula:Time = distance/speed Solution : Time = 30 mi/ 10 mi/ hr It will take 3 hrs for the train to travel a distance of 30 miles
LEARNING ACTIVITY SHEET Learning Area: Science Quarter: 3rd Quarter Lesson No.: 5 Date: Lesson Title/ Topic: Motion (Speed or Velocity) Name: Grade & Section: I. Activity No. 5.2: Speed/ Velocity Calculations (20mins ) II. Objective: After this activity, you should be able to solve problems involving speed and velocity III. Materials Needed:paper and pen
IV Instructions: Solve the following problems on Speed and Velocity. Show your complete solution with proper units. ( Note: Round off your answers to 2 decimal places ) A football field is about 100 m long. If it takes a person 20 seconds to run its length, how fast were they running ? If you drive at 80 km/ hr , North for 6 hours, what is your displacement ? A bullet travels at 850 m/s. How long will it take a bullet to go 750 m?